Itowns , BIM model and 3D Object

[sis-irenee]

Hello everybody,
I am currently working, as part of my end-of-study project, on the integration of a BIM model and a point cloud in a web GIS environment. We work with Revit (for the BIM part) and Itowns (for the web part).

I converted my mockup to FBX (from Révit) and then converted it to DAE (with an online converter) to be able to view it in Itowns.
However, I encountered some problems when integrating my model :

• the model is much too large, so I have to apply a scale factor to have it the right size,
• Georeferencing level, I have to do it manually so that the model is in the right position. However, there is a risk of loss of precision,
• Finally, I want to be able to query elements of my model but that is impossible with this format because it does not contain any information such as for example a 3dtiles.

I have found a few alternatives but they don't really work well.

my question is:

• how to automatically georeference a 3D object in Itowns (or at worst damage it)
• Is there another more suitable format for viewing BIM in Itowns ?

NB: I am currently processing the passage IFC-CityGML- 3D tiles.

I've been struggling a bit with it for 2 months, so any help will be welcome (link, techniques, ideas, etc).
thank you so much.

exemple.txt

[gchoqueux]

Hello,

You could use FBXLoader instead of Collada loader.

how to automatically georeference a 3D object in Itowns (or at worst damage it)

For GlobeView, you have to convert the projection to EPSG:4978.
You could use PlanarView if your original projection is conic (Lambert)

Is there another more suitable format for viewing BIM in Itowns

3D tiles is the best format

I come back to you to give you a process to convert to 3d tiles

[sis-irenee]

Hello,
thank you for the answer, I will test on my model.

I am going to test FBXLoader, because with Collada I have to apply a scaling factor.

my model is georeferenced in RGF93 CC49.

ok I await your feedback regarding 3D tiles